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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 536.3 km/sec
density: 0.2 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: C6
2058 UT Sep27
24-hr: C6
2058 UT Sep27
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 27 Sep 11
Sunspot 1302 poses a continued threat for X-class solar flares. Credit: SDO/HMI
Sunspot number: 103
What is the sunspot number?
Updated 26 Sep 2011

Spotless Days
Current Stretch: 0 days
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 26 Sep 2011

The Radio Sun
10.7 cm flux: 148 sfu
explanation | more data
Updated 26 Sep 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 7
explanation | more data
Interplanetary Mag. Field
Btotal: 5.5 nT
Bz: 3.2 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 27 Sep 11
A solar wind stream flowing from the indicated coronal hole could reach Earth on Sept. 30th-Oct. 1st. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Sep 27 2210 UTC
0-24 hr
24-48 hr
40 %
40 %
25 %
25 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2011 Sep 27 2210 UTC
0-24 hr
24-48 hr
15 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
05 %
05 %
01 %
01 %
01 %
Tuesday, Sep. 27, 2011
What's up in space

Are we alone? Your iPhone has the answer. Download the all-new Drake Equation app to calculate the population of the Milky Way.

DrakeEQ for iPhone and iPad

UARS RE-ENTRY ZONE: NASA has released a new statement pinpointing the re-entry of the UARS satellite on Sept. 24th: "The Joint Space Operations Center at Vandenberg Air Force Base in California has determined the satellite entered the atmosphere over the Pacific Ocean at 14.1 degrees south latitude and 189.8 degrees east longitude . This location is over a broad, remote ocean area in the Southern Hemisphere, far from any major land mass. The debris field is located between 300 miles and 800 miles downrange, or generally northeast of the re-entry point. NASA is not aware of any possible debris sightings from this geographic area." [more]

SUBSIDING STORM: A severe geomagnetic storm (Kp=7 to 8) that began yesterday when a CME hit Earth's magnetic field is subsiding. At the peak of the disturbance, auroras were sighted around both poles and in more than six US states including Michigan, New York, South Dakota, Maine, Massachusetts and Minnesota:

"The evening started off beautifully here in northeast Minnesota," says Travis Novitsky, who photographed the display from Grand Portage. "Almost as soon as it was dark we were seeing tall columns of green and red light. It was brief, yet spectacular!"

Sky watchers at the highest latitudes should remain alert for auroras as Earth's magnetic field continues to reverberate from the CME impact. Aurora alerts: text, voice.

more images: from Aleksander Chernucho of Kola peninsula, Russia; from Minoru Yoneto of Queenstown, New Zealand; from Beatrice van Eden of Antarctica; from Douglas Kiesling of Osakis, Minnesota; from Vanessa Gervais of Chisasibi, Quebec, Canada; from Bjørnar G Hansen of Kvaløya, Norway; from Steven Graham of Christchurch, New Zealand; from Mika Puurula of Sotkamo, Finland; from Jonathan Tucker of Whitehorse, Yukon; from Julius Jahre Sætre of Vestfold, Norway; from Sternwarte Riesa of Segelflugplatz Riesa/ Canitz, Germany; from Elizabeth Gyurgyak of Tananger, Norway; from Reed Ingram Weir of Northumberland, UK; from Krzysztof Polakowski of Rimforsa, Sweden; from Thilo Bubek of Tromsø, Norway; from Bjarne Riesto of Varanger, Norway; from Marek Nikodem of Szubin, Poland;

BIG SUNSPOT: The source of all this solar and geomagnetic activity is sunspot AR1302. Measuring more than 150,000 km from end to end, the sprawling active region is visible even without a solar telescope. Fabiano Belisário Diniz saw it plainly in last night's sunset from Curitiba, Brazil:

"It was overcast and cold all day long, but at the end of the day a break in the clouds revealed the sun and AR1302," says Diniz. "What a great sight!"

The sunspot has quieted down since unleashing dual X-flares on Sept. 22nd and 24th. Nevertheless, NOAA forecasters estimate a 40% chance of more X-flares during the next 24 hours. Any such eruptions would be Earth-directed as the sunspot crosses the center of the solar disk. Solar flare alerts: text, voice.

more images: from Ali Norouzi of Karaj, Iran; from Stefano Sello of Pisa, Italy; from Phil Greaves of Sydney Australia; from Stefan Plach of Stadt Wehlen, Saxony, Germany; from Monty Leventhal OAM of Sydney, Australia; from Rogerio Marcon of Campinas SP Brasil; from Francisco A. Rodriguez of Cabreja Mountain Observatory, Canary Islands;

September 2011 Aurora Gallery
[previous Septembers: 2010, 2009, 2008, 2007, 2006, 2005, 2004]

  Near Earth Asteroids
Potentially Hazardous Asteroids (PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time.
On September 27, 2011 there were 1250 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 SQ32
Sep 20
7.5 LD
44 m
2011 SK68
Sep 21
5.8 LD
13 m
2007 TD
Sep 22
6.2 LD
58 m
2011 SE58
Sep 27
0.6 LD
13 m
2011 SO5
Sep 29
5.6 LD
34 m
2002 AG29
Oct 9
77.1 LD
1.0 km
2011 SE97
Oct 12
7.9 LD
52 m
2011 SS25
Oct 12
70 LD
1.2 km
2000 OJ8
Oct 13
49.8 LD
2.4 km
2009 TM8
Oct 17
0.9 LD
8 m
2011 FZ2
Nov 7
75.9 LD
1.6 km
2005 YU55
Nov 8
0.8 LD
175 m
1994 CK1
Nov 16
68.8 LD
1.5 km
1996 FG3
Nov 23
39.5 LD
1.1 km
2003 WM7
Dec 9
47.6 LD
1.5 km
Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach.
  Essential web links
NOAA Space Weather Prediction Center
  The official U.S. government space weather bureau
Atmospheric Optics
  The first place to look for information about sundogs, pillars, rainbows and related phenomena.
Solar Dynamics Observatory
  Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  from the NOAA Space Environment Center
  the underlying science of space weather
Science Central
Conquest Graphics
  for out-of-this-world printing and graphics
Trade Show Displays
  more links...
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